Engine starting mechanism



April'4, 1939. c. R; WASEIGE 2,152,675

' ENGINE STARTING MECHANISM I Filed June 29, 1935 2 Shets-Sheei 1INVENTOR. Char/es fia ymo/m Wax/7e ATTORNEYS,

April 4, 1939. c. R. WASEIGE ENGINE STARTING MECHANISM Filed June 29,1935 2 Sheets-Sheet 2 INVENTOR. Char/es Raymond M ase BY m 5 1r 5ATTORNEYS.

Patented Apr. 4, 1939 PATENT OFFICE.

ENGINE STAR/[IN G MECHANISM I Charles Raymond Waseige, Rucil, France,as-

signor to Societe Air Equipment Billancourt, Seine, France, a Frenchcompany Application June 29, 1935, Serial No. 29,162

In France July 24, 1934 2 Claims. (01. 123-479 This invention relates toengine starting mechanism and more particularly, through notexclusively, to starting apparatus of the inertia y The starting. ofexplosion engines, and particularly the engines of aeroplanes, requireseither, in the first place, that an important muscular effort bedeveloped to turn the engine over by hand, or to rotate at a sufficientspeed a fly Wheel the live force or energy of which will be subsequentlyutilized to turn the engine, or, in the second place, requires theprovision of important sources of energy either of the electric or ofthe compressed fluid form. Now it must 15 be borne in mind that the lastsolutions envisaged are accompanied with a large dead weight, demand aperiodic recharging, and, in the case of batteries, it is necessary, inorder that their proper functioning be assured, that the utilizationthereof be not interrupted for long periods of time. These requirementsare not easily fulfilled when it is a question of private aeroplanes,and as concerns military aeroplanes, the fulfilment of theserequirements necessitates the maintenance on hand of a large reserve ofmaterial.

The present invention relates to apparatus for the starting of theengines by inertia and has for object the improvement of these devicesfor the purpose of eliminating the drawbacks hereinbefore set forth. Tothis end, and this constitutes one of the principal, but not the onlyimportant characteristic of the present invention, the auxiliary sourceof energy for rotating the flywheel or inertia element is provided by asmall such a motor, it is obvious that it is easily started by hand andfor this reason numerous advantages as to weight. space-takeup andfacility of utilization are provided.

According to another characteristic of the invention, the organ thatcouples the flywheel to the engine to be started is automaticallycontrolled so as to effect the coupling at the moment desired throughthe intermediary of a quick release mechanism actuated either by acentrifugal regulator connected for rotation to the flywheel or to themotor, or by a pawl-ratchet device or any similar step by step orprogressive advance mechanism which operates as a function of the numberof turns eifected by the flywheel or the motor. In any event thestarting motor may be 5 left in gear in order that the couple developedthereby may support and bolster up the. energy engendered in theflywheel or contrarily a liaison may be provided between a couplingdisposed between the flywheel and the source of starting en-. ergy andbetween the automatic clutch mechanism connecting the engine to bestarted to the flywheel in such a way that the starting motor isautomatically disengaged, a disposition which constitutes anothercharacteristic of the present invention.

In the last mentioned case, it is advantageous to provide automaticignition interrupting means or mechanism controlling automatically thethrottle of the starting motor in order that, after the starting of theengine, the starting motor may be automatically stopped or brought toidling speed.

In the last case envisaged the starting motor continues to -rotateslowly with just sufficient energy to overcome the cylinder compressionand is only stopped definitely when the engine has effectively startedand when it is determined that it will be no longer necessary to rebuildup energy in the flywheel.

For the purpose of more rapidly bringing the flywheel to its desiredspeed for starting the engine, it may be advantageous to provide a speedchange mechanism between the flywheel and the starting motor. This speedchange mechanism may be actuated automatically bythe centrifugalregulator hereinabove mentioned or by a device which operates as afunction of the number of turns effected by the starting motor.

For the event in which the starting attempt has been unsuccessful, it isnecessary to be able to liberate the coupling between the starting motorand the engine to be started for the purpose of rendering possible a newrotation and building up of energy in the flywheel. In the case wherethe coupling takes place by the axial displacement of a pinion, ahelicoidal member or the like,

it is absolutely necessary to disengage this pinion. To effect this end,means are provided to permit turning by hand of the helicoidal member ina sense inverse to that communicated to it by the starting motor.

In one embodiment for the realization of this end, utilization is madeof a three-position crank for the rotation of the starting motor, thecrank permitting the rotation thereof in either direc- 10 For thepurpose of a clearer understandingof the subject matter of the presentinvention, ref erence is had to the accompanying drawings, wherein:

Figure 1 is a view in elevation of the starting mechanism;

Figure 2 shows an automatic control for the clutch that is adapted toconnect the starting motor to the engine to be started when the formerhas effected a predetermined number of turns.

Figure 3 is a change speed mechanism between the starting motor and theflywheel.

Figure 4 is a plan view in large scale of a device for the starting ofthe starting motor.

I indicates, in Figure l, the crankshaft of the motor to be started. 2is the inertia flywheel which is adapted to be rotated at a high rate ofspeed in order that sufficient live force may be built up therein toeffect the turning over of the motor to be started. The flywheel may be80 mechanically connected to the crankshaft I through the intermediaryof a set of reduction gearing indicated in general by the referencenumeral 3. The transmission between the flywheel and the crankshaft Icomprises a screw pinion 4 carried by a screw 5 freely mounted on anaxis of the said transmission, but capable of being connected to thataxis by a dog clutch 6, for example, comprising a dog I splined to butlongitudinally slidable upon the axis. The dog may be displaced upon theaxis by means of a pull mechanism 8 provided with a spring.

According to the invention, the rotation of. the

flywheel 2 is assured by a small explosion or internal combustion motor9 carried-conveniently,

for example, directly by the housing I0 which encloses the transmission3, the housing I 0 being fixed to the housing II of the engine to bestarted. The starting motor 9 may be of any suitable type, but should beas light as possible and should be able to develop a high angular speed.This solution permits a more rapid rotation of the flywheel than thedevices heretofore provided, thus requiring a less important gear trainbetween the starting motor and the flywheel. In the present instance,the connection between the motor 9 and the flywheel comprises a clutchI2 hand operated through the intermediary of a pull member I3 and themotor is started by the hand crank I 4 represented as being disposed onthe motor itself. It is is nevertheless an advantage in that it permitsan easier starting of the motor 9 which, by reason thereof, may becompletely isolated from the transmission 3/ For the purpose ofeffecting the automatic coupling of the starting mechanism with thecrankshaft I of the engine to be started, in other words to bring aboutautomatically at the desired moment the manoeuvre of the pull member 9,utilisation is made of a device I5 providing a sudden release, thedevice being controlled by The presa rod I6. Referring to Figure 1, itcan be noted that this rod is actuated by a centrifugal regulator I'Imotivated from one of the organs that the starting motor rotates. Asindicated, the regulator may be conveniently operated from one of .thetransmission gears between the flywheel and the shaft I. Thedisplacement of the rod I6 in the sense corresponding to the engagementis effected against the action of a spring I8. It

will be readily understood that when the motor 9flywheel 2 organizationhas reached a predetermined speed, the rod I6 has taken a position inwhich the quick release bell crank I5 is on the point of coming intooperation to effect a single pull on the pull member 8, the displacementof which is communicated to the jaw I. This jaw comes into engagementwith the screw 5 and as a consequence thereof the shaft I is therebybrought into rotation by the flywheel 2.

For the case in which it is desired to isolate automatically thestarting motor 9, one can, as indicated by the Figure 1, utilize forthis purpose the displacement of the rod I6. The rod in its displacementcauses operation of a rapid release bell crank I9 similar to I5, therapid release device I9 coming into operation against a shoulder 20 ofthe rod I3 so as to produce a rapid disengagement at I2, simultaneouslywith, or slightly after the device I5 has effected, as hereinbeforeindicated, the connection between the starting motor and the shaft I ofthe engine to be started.

The idling, and eventually the stopping, of the starting motor in thecase of'the declutching of the latter is assured automatically by aconnection between the throttle of the motor 9 and the clutch mechanismI2. To this end the rod I3 carries a shoulder I 3a which, in thedisengaged position, rests! upon a swinging lever 2I that is connectedby rodding 2Ia to a lever 2|! connected to the throttle.

The connection comprises a certain amount of plates disposed in suchmanner that the throttle can be opened to its maximum extent withoutaffecting the rod l3. One can thus assure the causing of the-motor toidle by means of a rapid release device acting on .the lever 2Ib andcontrolled by the rod I6.

In any event the shaft I turns so long as the live force of the flywheel2 is not exhausted. If

the engine starts, the screw pinion ,4 displaces itself automatically inthe direction of the arrow i along the screw 5 and the mechanicalconnection between the starting mechanism and the engine is interrupted.All that remains necessary is to stop the starting motor either by handor automatically. For the realization of this end in the embodimentillustrated in Figure ,1, the

screw pinion 4 in displacing itself in the sense of the arrow ,1, causesthe lever 22 to swing which, through the intermediary of a linkage 23and an appropriate mechanism actuates the rod 24 in the direction f1whereby the throttle of the starting motor is closed and the motorstops.

If the engine. does not start, the rod I6 returns to its originalposition under the action of the spring I8 according as the elementwhich effects rotationof the regulator I'I slows down. Through theeffect of thisreturn movement. of the rod I6 the device I5 swingssuddenly at a given moment in the direction opposite to the arrow f2'and permits the spring of the pull member 8to interrupt the connectionbetween the nut 1 and the screw 5. The mechanism now lends itself to anew starting attempt, but as the screw pinion 4 has remained in gearwith-the engine to be started, any failure of the gearing elements toslip with'suflicient freedom might cause a breaking of gear teeth. As afurther, although not absolutely rigid and unyielding safeguard.

For this purpose there is provided a swinging v lever 24a the extremityof which in the form of a fork engages with a trunnion of the rod 23..Coaxially to the lever 24a is mounted another lever 24b drawn towardlever 24a by a 'spring24c. The

. arrangement is such that when the rod 23 is in of the lever 2411 comesinto position on this' trajectory between the positions of the shoulder24d corresponding to the engagement and to the disengagement of thecoupling l2. Furthermore, the trajectory of the extremity of the lever24b does not encounter the shoulder 24d for the position ofdisengagement of the rod I 3. It results therefore, as in the positionindicated in Fig, 1, that the lever 24b opposes itself to the engagementof the coupling l2, but before this occurs the rod 13 is allowed to comeback to its position corresponding to disengagement against the eifortof the spring 24c and as a result of the push of the shoulder 24d in thecourse of the disengagement of the coupling I 2.

For the purpose of absolutely disengaging the screw pinion 4 recoursemay be had to a threeposition crank (Fig. 4) for the starting of themotor 9, one neutral position being provided and two other positionspermitting the motor to be turned in opposite directions. The hand crankl4 carries on its opposite faces the toothings 30 and 3| cooperatingrespectively with two other toothings 32-33 fixed to or forming part ofthe motor shaft, the hand crank being normally maintained in its mediumneutral position by the opposed springs 3435. .All that is necessary todisengage the pinion 4 and permit a new attempt of starting is to turnthe engine in its non-normal sense.

For the purpose of permitting the rotation at will and by hand of theengine to be started in utilizing the hand crank i4,-there is hereprovided a link |5a articulated on a lever I517 angularly fixed withrespect to levers I50 and l5d of the quick release device 15 whichcontrols the clutching of the engine to be started to the inertiaflywheel. This clutch can be thus controlled at will and by handindependently of the automatic control provided therefor.

Figure 2 shows another form of embodiment of automatic control of therod 16 in function of the number of turns efiected by the starting motor9 or of the flywheel l. In this embodiment the shaft of the startingmotor 9 or the transmission to the flywheel motivates, through theintermediary of a reduction gearing 25, here illustrated as of the wormtype, a threaded shaft 26 that is axially fixed and along which maydisplace a half screw 21 guided in such a way that it cannot turn. Twotrunnions carried bythis screw 21 are engaged by a fork-28 provided atthe extremity of one arm of a two-armed lever of which the other arm isarticulated on the rod 16. It a .the action of the motor 9 thereon.

will be understood that at the end of a definite or determined number ofturns the rod I6 comes into the position for which take placeautomatically the operations hereinabove set forth for the control bythe centrifugal regulator.

' The guide bar 36 of the screw 21 is carried at its extremity by twolevers31 that are arranged to pivot about the same axis in order topermit the disengagement .of the screw 21 from the threaded shaft 26 anda spring 38 is provided which continually urges the screw 21 in thesense contrary to the displacement which results from It is obvious thatwhen the connection between the screw 21 and the threaded shaft 26 isinterrupted by the raising of the screw, the latter is returned alongthe bar 36 by the "spring 38 and comes back into its initial positionbringing with it the rod'l6 through the intermediary of the lever 29.The raising of the screw 21 is obtained in this embodiment through anydesired mechanismas for instance. throughthe intermediary of a Bowdencable, but it is to be understood that the operation may be effected byany other mechanism adapted to the conditions imposed.

Referring. to Figure 3, there is provided an embodiment of an automaticchange speed disposed between the starting motor and the fly- 'wheel. Inthis embodiment a planetary gear train is utilized of which one of theplanetaries 40 is connected to rotate with the flywheel 2 while theother planetary may be immobilized or connected for rotation to theshaft 42 of the starting motor 9 through the intermediary, for example,of a jaw clutch of which one of the jaws is displaceable and splined tothe tail of the planetary 4|. The movable jaw carries two oppositetoothings 43 and 44 adapted to be brought respectively into engagementwith two toothings 45 and 46, the one 45 fixed to the housing and theother 46 carried by a plate of the shaft 42. The

satellites 41 are always set in motion directly by the shaft42 of thestarting motor.

The engagement in one sense or in the other is controlled by a quickrelease device 48 that is actuated automatically by a cam 50 motivatedby the mechanism which controls the rod l6. In the embodimentrepresented this cam 50 is carried by the rod 16. It is obvious thatwhen toothings 43 and 45 are in engagement, the shaft of the flywheel isrotated with a certain reduction by the shaft 42 whilst, when thetoothings 44 and 46 are in engagement, a direct coupling between theshaft 42 and the flywheel 2 results. The first position corresponds tothe getting under way of the motor 9 and of the flywheel 2. Then, whenthe flywheel and the motor have acquired a certain predetermined speedor eifected a number of turns chosen in advance, the cam 50 actuates themechanism 48 which releases and brings into engagement the toothings 44and 46 eifecting thus the'direct connection between the driving shaftand the driven shaft.

. It is to be clearly understood that the invention is not limited tothe mechanical embodiments and details of realization represented anddescribed, which, by the way, have been suggested merely as exemplary,the scope of the present invention being defined only by the claimshereto f pended.

What I claim is:

1. A starting mechanism for aircraft engine comprising a flywheel, adriving motor, means including a. clutch for drivably connecting saidmotor to said flywheel, an engine engaging memclutch, means foryieldably opposing movement of said clutch shitting member, and meansshiftvable with said engine engaging member for withdrawingsaidiopposing means from the opposing 1 {)OSlti-Oll. i

2. A starting mechanism for aircraft enmes comprising: a flywheel andpower means for actuating said flywheel, means including a clutch v anda self engageable and disengageable pinion to cause operative connectionof the fly wheel with the engine to be started so that the latter may beturned over by said fly-wheel. and means responsive to the position ofthe pinion to yieldably oppose reoperation oi .the starting mechanism.

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